From the Guidelines
Biphasic T waves are a significant ECG finding that warrants prompt clinical evaluation for potential myocardial ischemia, particularly in the context of acute coronary syndrome or Wellens' syndrome, as they may indicate critical stenosis of the left anterior descending coronary artery and precede an anterior wall myocardial infarction. These findings are characterized by T waves that have both positive and negative components, appearing as if the T wave changes direction during its course 1. The presence of biphasic T waves suggests abnormal ventricular repolarization due to compromised blood flow to the myocardium. According to the guidelines for unstable angina/non-ST-segment elevation myocardial infarction, a 12-lead ECG is crucial in detecting ACS, and T-wave inversion on the initial 12-lead ECG portends a less-adverse prognosis in patients with ACS 1.
Some key points to consider in the evaluation and management of biphasic T waves include:
- Urgent cardiac evaluation including cardiac biomarkers (troponin) and additional ECG monitoring
- Cardiac catheterization to assess coronary anatomy if indicated
- Management targeting the underlying cause, which may include antiplatelet therapy (aspirin 81-325mg daily), anticoagulation, beta-blockers, and revascularization if indicated
- Recognition that biphasic T waves can occasionally appear in healthy individuals, particularly in certain ECG leads, but widespread or new biphasic T waves should never be dismissed without thorough investigation 1.
It is essential to approach patients with biphasic T waves with a high index of suspicion for underlying coronary artery disease and to prioritize their evaluation and management accordingly, given the potential for significant morbidity and mortality associated with untreated myocardial ischemia 1.
From the Research
Biphasic T Waves
- Biphasic T waves are not directly mentioned in the provided studies 2, 3, 4, 5, 6
- The studies focus on the diagnosis of myocardial ischemia using various methods such as exercise electrocardiography, stress echocardiography, and stress imaging techniques
- The studies discuss the diagnostic accuracy and efficiency of these methods, but do not specifically address biphasic T waves
- Some studies mention the importance of interpreting ST-segments and wall motion abnormalities in the diagnosis of myocardial ischemia 3, 4, 5
- However, there is no direct reference to biphasic T waves in the provided studies, suggesting that this topic may not be directly related to the diagnosis of myocardial ischemia using these methods 2, 3, 4, 5, 6
Related Concepts
- Myocardial ischemia diagnosis using exercise electrocardiography and stress echocardiography 2, 3, 4, 5
- Stress imaging techniques such as myocardial scintigraphy, stress-echocardiography, and stress magnetic resonance imaging 3, 4, 6
- Diagnostic accuracy and efficiency of these methods in detecting myocardial ischemia 2, 3, 4, 5, 6